More about stuck seatposts

More details on removing a stuck seatpost. Reader Andrew Livingston has refined the information Matt Duff sent us on using caustic soda to dissolve (yes, dissolve!) a stuck aluminum seatpost in a steel frame.

5 Responses to More about stuck seatposts

I don’t have any contact info for Witold Walkowski so thought I’d try you
(or at least see if you could forward this to Witold).

I ended up using a penetrating oil called PB Blaster simply because I had some. I researched and found various companies advertising oils which they claimed worked with all materials. I emailed some with photos of my bike and my concerns about structural damage or paint destruction and got two replies.
One company “corrosionfree.com” recommended their product “Nut Z Lube” and suggested it be sprayed if possible both from top and from bottom and left overnight to soak in.
One company “pipebreakusa.com” recommended their product and Pipe Break and per their letter stated “I spoke to the chemist just a bit ago and he says that Pipe Break should work on your aluminum bike without a problem. He did state that he didn’t feel there would be any negative effect on the aluminum itself”
Had the PB Blaster not worked, I would have ordered the Pipe Break just because of the confidence in the statement that it should work without a problem. I haven’t used either product so I can’t warranty either.

Witold was discussing removing a seatpost from a carbon fiber frame. Yours evidently is aluminum. I would still be extremely wary of using any kind of penetrating oil on carbon fiber, because the epoxy could soak it up, and expand.

Did you get my full email? The above post is missing half of what I sent you.

I had got to the point where I was able to get the seat post to turn but can’t pull it out and was seeking clarification on his statement “I took two aluminum plates that just fitted nicely between the seat rail clamp plate and the top of the seat tube (one plate on one side of the seat post and the other on the opposite), with the seat rail clamp screws extended by a few turns. Then I gently turned the rail clamp screws in and the seat post just came out without any struggle 🙂 🙂 🙂 I did not apply any more force then, just slight finger pressure on the Allen key while turning the screws. I am sure that a similar method may be used on metal frames and seat posts or any combination of the material. You just need the right length of spacer blocks or some kind of screw attachment to do the pushing off the seat tube from the seat post ”

I don’t want to try to pull the seat post out and deform the seat tube.

Witold Walkowski, who composed that section, improvised a mechanism to push down on the top of the seat tube while pushing up on the underside of the saddle clamp by using the bolts of the saddle clamp itself to apply force. YMMV depending on the type of saddle clamp.